code: def resolve_files(
      data_frame: pd.DataFrame,
      key: str,
      root: PATH_TYPE,
      resolver: Callable[[Optional[PATH_TYPE], Any], PATH_TYPE],
  ) -> List[PATH_TYPE]:
      """Resolves a list of files from a given column in a data frame.
  
      Args:
          data_frame: The ``pd.DataFrame`` containing file IDs.
          key: The column in the data frame containing the file IDs.
          root: The root path to use when resolving files.
          resolver: The resolver function to use. This function should receive the root and a file ID as input and return
              the path to an existing file.
  
      """
      if resolver is None:
          resolver = default_resolver
      return data_frame.apply(
          partial(_resolve_file, resolver, root, key), axis=1
      ).tolist()
  
file_path: lightning-flash/src/flash/core/data/utilities/data_frame.py
imports: import os
  from functools import partial
  from typing import Any, Callable, List, Optional, Union
  import pandas
  from flash.core.data.utilities.paths import PATH_TYPE
label_desc: Use image node_id 5 for calling a global function with example usage: resolve_files(data_frame, key, root, resolver) and returns: data_frame